Reactive hot melt moisture cure adhesives are typically solid and nonreactive at typical ambient temperatures. The adhesives, however, when heated to a melt temperature can be extruded onto a work piece with other components to form an initial “green bond” that can subsequently be cured to form a rigid, mechanically stable bond after cooling. In the assembly of a final unit, the adhesive preferably can be easily applied at melt temperature, and can be compatible with the work piece surfaces. When assembled into a unit including two or more work piece surfaces and an adhesive bond, the material must maintain both a high “green strength” (cohesive strength of the adhesive prior to cure) and a permanent adhesive bond when cure is complete. Green strength is important to maintain the structural integrity of the work piece during manufacture. Any substantial relative movement of the work pieces in the assembled unit can result in substantially reduced productivity or non-workable products.
We have found in many industries a substantial need for an improved hot melt moisture cure reactive hot melt adhesive that can be used in a variety of end use applications, typically in unit product assembly, which has beneficial properties in ease of application at melt temperature, high green strength after application and substantially improved strength after curing.